The objectives of Core B are to provide Imaging services, antibodies, and antibody production services to the individual components of the Program Project. At the request of the other Pis, Dr. Sakai will discuss experiments, devise appropriate experimental strategies and protocols, and then perform agreed upon services. Imaging Services: Transmission electron microscopy (including immunolocalization as well as standard ultrastructural imaging) and confocal microscopy are available to all of the Projects. Antibodies: The following well-characterized antibodies will be distributed to the Projects upon request: rabbit polyclonal antibodies specific for fibrillin-1, fibrillin-2, LTBP-1, and LTBP-4;monoclonal antibodies specific for fibrillin and for BMP-7. These antibodies are all suitable for use with mouse materials. In addition, the Core can provide monoclonal antibodies specific for flbrillin-1, fibrillin-2, and fibrillin-3, and for elastin, which react with human, bovine, and avian fibrillins. The Core has also produced and characterized monoclonal antibodies specific for human fibulin-4. Custom-made antibodies: Rabbit polyclonal or mouse monoclonal antibodies can be generated, in consultation with Project Pis. Project Pis will provide the immunogen and will also perform some assistance with antibody screening and characterization. Because commercial sources of pSmad 2/3 antibodies have been unreliable and inconsistent, we will synthesize phospho-Smad peptides to use as immunogens, generate and characterize our own reliable pSmad2/3 antibodies. Recombinant proteins: Limited supplies of recombinant proteins are also available. These include recombinant fibrillin-1 and fibrillin-2 polypeptides;recombinant LTBP-1, LTBP-2, LTBP-3 and LTBP-4 polypeptides;and recombinant BMP-7.